In a medium bowl, combine sour cream, egg yolks, sugar, yeast, lemon zest, vanilla, and salt.

Mix it well together using a whisk or hand mixer.

In a separate bowl, combine butter and flour.

Slowly add the flour combined with butter to the rest of the ingredients, and using your hands, knead all the ingredients until well combined.

Cover the dough with a plastic wrap and place it in the fridge for at least 2-3 hours. You can also leave it overnight.

When you're ready to bake your Rugelach cookies, start by preheating the oven to 350° Fahrenheit or about 180° Celsius.

Remove the dough from the fridge and take half a portion of the dough.

Using a rolling pin, roll out the dough into a circle of about 12 inches in diameter or about 30 cm.

Using a pizza cutter, cut off the uneven edges and then cut the circle in eight equal slices.

Take plum butter and using a butter knife spread about a teaspon of plum butter on each piece.

Roll each piece from outside in and then twist gently into a crescent.

Repeat for each piece to form your Rugelah cookies and place them on a cookie sheet lined with perchament paper. You should get a batch of about 24-26 cookies.

Bake for 20-25 minutes maximum.

Sprinkle the cooled cookies lightly with some powdered sugar.